Research efforts in our laboratory are directed towards understanding the molecular mechanisms regulating spatial communication between the cytoplasm and the nucleus in plant cellular immunity to pathogenic microbes, using Arabidopsis as model organism. Here, we employ biochemical, cell biological, genetic and molecular approaches to study the functions of nuclear transport receptors (NTRs) and nuclear pore complex proteins (Nucleoporins) that are essential for plant disease resistance and control nucleocytoplasmic trafficking of proteins and RNAs. Our studies further include in planta affinity purification approaches, forward and reverse genetics to identify novel biochemical and genetic interactors required for plant defense. Another line of research is aimed at exploring in planta molecular functions of secreted fungal effector proteins that are targeted into host cell nuclei during infection and at identifying respective host cell NTRs that mediate nuclear effector translocation.